Spoolers for sewing threads and the like must, if they are to operate economically, be operated with downtimes which are as short as possible. This applies not only to replacement of already finish wound spools or bobbins during winding of a load, but also for the changing of the load because here, as a rule, the operating parameters of the spoolers have to be newly adjusted.
In the fabrication of high quality threads or yarns, yarn defect sensors are provided at the spool units of spoolers, which react to defects of the thread to be wound by the spool unit. A defect classification device classifies the registered thread defects and subdivides the thread production into several quality classes. Apart from the quality class "defect-free thread", one can classify quality classes, in which the thread has defects, which, to be sure, permit further processing, however, if they occur too often, lead to problems, such as with respect to sewability or to optical discrepancies. As the lowest quality class, it is possible to register defects in which the thread cannot be processed further, for instance, since it contains thickened spots which can lead to needle fractures. In particular, in case of defects of the last mentioned type, the classification device stops the spool unit, so that the thread can be cleaned up, for instance, by cutting out and reknotting or splicing of the cutout spot.
In spoolers comprising such classification devices, a very high quantity of operational parameters must be preset, so that the setup of the spooler is relatively time consuming. Conventional spoolers do not operate during the setup operation. Further, essential downtime results at the termination of the load since the operational parameter set is associated with a large number of spool units, if not the entirety of the spool units, and with conventional spoolers, one has to wait until the last spool of the load is wound up before the new operational parameter sets can be set up. In the most unfavorable cases, this can lead to a predominant number of the spool units of the machine being idle for periods exceeding an hour, while merely several spool units are finish winding the load.
It is an object of the present invention to show, by way of a simple design, how downtimes of a thread spooler can be reduced during change of the loads to be wound or rolled up and, at the same time, to increase the operational dependability of the machine.